@aVar - Thank you for reaching out to us and being patient while we were working on resolving this issue for you.
Thank you for confirming with our support after all the troubleshooting and debugging, that you were successfully able to deploy the template while migrating from azure classic VM to ARM.
Reason for the issue is that the fabric was taking too long to delete a resource, and RDFE failed. Actions need to be taken on the backend to clear out a couple of commit "stuck" failures. After that, you can try to remigrate, and it should deploy as expected.
If you have any further questions, please feel free to reach out to us and will be happy to help.
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